Events during upload

The following pseudocode illustrates how upload events and upload scripts are invoked. The pseudocode uses the following conventions:

A script is real This means the script is defined as a real script that will be executed against the consolidated database during synchronization.
A script is defined as an ignored script This means the script is defined as an ignored script using "--{ml_ignore}".
A script is defined This means the script is defined as a real or an ignored script.
A script is not defined This means there is no script defined for the event at all. You must ignore a script if it is a required script, but you do not want to use that script.

These events take place at the upload location in the complete event model. See Overview of MobiLink events.

Overview of the upload

------------------------------------------------------
upload
------------------------------------------------------

begin_upload // Connection event
for each table being synchronized {
  begin_upload // Table event
}
  handle_UploadData
  for each table being synchronized {
    begin_upload_rows
    for each uploaded INSERT or UPDATE for this table {
      if( INSERT ) {
        <upload_inserted_row>
      }
      if( UPDATE ) {
        <upload_updated_row>
      }
    }
    end_upload_rows
  }
  for each table being synchronized IN REVERSE ORDER {
    begin_upload_deletes
    for each uploaded DELETE for this table {
      <upload_deleted_row>
    }
    end_upload_deletes
  }
 
For each table being synchronized {
  if( begin_upload table script was processed ) {
    end_upload // Table event
  }
}
if( begin_upload connection script was processed ) {
  end_upload // Connection event

  for each table being synchronized {
    upload_statistics  // Table event.
  }
    upload_statistics  // Connection event.

  COMMIT

Upload inserts

------------------------------------------------------
<upload_inserted_row>
------------------------------------------------------
// NOTES:
// - Only table scripts for the current table are involved.

 ConflictsAreExpected <- (
    upload_new_row_insert script is defined or
    upload_old_row_insert script is defined )
if( upload_insert script is real ) {
    upload_insert
} else if( ConflictsAreExpected and
    upload_update script is not defined and
    upload_insert script is not defined and
    upload_delete script is not defined ) {
    // Forced conflict which is deprecated
    if( upload_new_row_insert script is real ) {
        upload_new_row_insert
        resolve_conflict
    } else if( upload_new_row_insert is defined as an ignored script ) {
        // Ignore this insert
    } else {
        error
    }
} else if( handle_uploadData script is real or
    upload_insert script is defined as an ignored script ) {
    // Ignore the insert. (Only ignored in SQL, possibly handled by handle_uploadData.)
} else {
    error
}

Upload updates

------------------------------------------------------
upload_updated_row
------------------------------------------------------
// NOTES:
// - Only table scripts for the current table are involved.
// - Both the old (original) and new rows are uploaded for
//   each update.

 ConflictsAreExpected <- (
   upload_new_row_insert script is defined or
   upload_old_row_insert script is defined )
Conflicted <- FALSE
if( upload_update script is real ) {
    if( upload_fetch script is real ) {
        if( ConflictsAreExpected ) {
            FETCH using upload_fetch INTO current_row
            if( current_row <> old row ) {
                Conflicted <- TRUE
            } else {
                upload_update
            }
        } else {
            error
        } 
    } else if( upload_fetch script is not defined ) {
        if( ConflictsAreExpected ) {
            // This conflict detection approach is deprecated
            upload_update
            if( number of affected rows is 0 ) {
                Conflicted <- TRUE
            }
        } else {
            // No conflict detection and resolution by the MobiLink server
            // The upload_update script should handle conflict detection and resolution
            upload_update
        }
    } else {
	// the upload_ftech script cannot defined as an ignored script
	error
    } 
} else if( ConflictsAreExpected and
    upload_update script is not defined and
    upload_insert script is not defined and
    upload_delete script is not defined ) {
    // Forced conflict which is deprecated
    Conflicted <- TRUE
} else if( handle_uploadData script is defined or upload_update script is defined as an ignored script ) {
    // Ignore the upload update (Only ignored in SQL, possibly handled by handle_uploadData.)
} else {
    error
}
if( Conflicted ) {
    if( upload_old_row_insert script is real ) {
        upload_old_row_insert
    } else if( upload_old_row_insert script is defined as ignored script ) {
        // Ignore the old value
    } else {
        error
    }
    if( upload_new_row_insert script is real ) {
        upload_new_row_insert
    } else if( upload_new_row_insert script is defined as ignored script ) {
        // Ignore the new value
    } else {
        error
    }
    if( no error ) {
        resolve_conflict
    }
}

Upload deletes

------------------------------------------------------
upload_deleted_row
------------------------------------------------------
// NOTES:
// - Only table scripts for the current table are involved.

  ConflictsAreExpected <- (
    upload_new_row_insert script is defined or
    upload_old_row_insert script is defined )
if( upload_delete is real ) {
    upload_delete
} else if( ConflictsAreExpected
    and upload_update script is not defined
    and upload_insert script is not defined
    and upload_delete script is not defined ) {
    // Forced conflict which is deprecated
    if( upload_old_row_insert is real ) {
        upload_old_row_insert
        resolve_conflict
    } else if( upload_old_row_insert is defined as an ignored script ) {
        // Ignore the delete
    } else {
        error
    }
} else if( handle_UploadData script is real or
    upload_delete script is defined as an ignored script ) {
    // Ignore this delete. (Only ignored in SQL, possibly handled by handle_uploadData.)
} else {
    error
}

Discuss this page in DocCommentXchange.